Dell says it has generated more than $3 million in sales that can be traced back to people responding to its Twitter posts. Sure, thatís a drop in the bucket for a company with revenue of about $12.3 billion in the first quarter of this year alone, but it suggests all sorts of possibilities for how the service may earn companies some money and is particularly interesting considering Twitter has yet to find a viable business model.

The computer manufacturer has been using the micro-blogging service to publicize deals and refurbished products at @DellOutlet since June 2007. This account now has more than 630,000 followers and is directly responsible for $2 million in sales, according to Dell; with a further $1 million reportedly coming from customers who use the @DellOutlet handle as an entry point into the companyís website before ultimately purchasing something from them.

Currently, Twitter is not charging companies for using its service to promote and make sales, but something like that could indeed be underway as the social network is reportedly soliciting feedback from Dell while testing out some new features together. Twitter is also said to be looking into real-time search advertising to make a profit.